Venturi Injection Versus Bubble Diffusers

Venturi Injectors

Example Ozone Injector / Venturi

Water flows from left to right; ozone is introduced into the middle.

Venturi Injectors work by forcing water through a conical body which initiates a pressure differential between the inlet and outlet ports. This creates a vacuum inside the injector body, which initiates ozone suction through the suction port.

Characteristics

• very high ozone mass transfer rate (up to 90%)
• requires water pump to initiate suction
• efficiency rarely decreases over time
• no moving parts

Venturi Injector Examples

Air being sucked into a venturi/injector - notice the thousands of small bubbles present after the suction port.

Injectors produce thousands of bubbles greatly increasing the surface area of oxygen, or ozone, in contact with the water. (Two small bubbles have greater surface are than one large bubble of the same volume.) This results in a very high mass transfer rate.

Bubble Diffusers

Bubble Diffuser Example

This is an example of a bubble diffuser bubbling ozone into an aqueous solution.

Bubble Diffusers work by emitting ozone through hundreds of bubbles beneath the water's surface.

Characteristics

• low ozone mass transfer rate (typically around 10-15%)
• efficiency increases with increased water depth
• requires air-pump to transfer oxygen below surface
• diffuser holes become fouled decreasing transfer efficiency

Ozone Transfer Efficiency
vs.
Flow Rate